Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,872   Posts: 1,583,470   Online: 1118
      
Page 2 of 2 FirstFirst 12
Results 11 to 19 of 19
  1. #11

    Join Date
    Jul 2010
    Location
    Southern USA
    Shooter
    Multi Format
    Posts
    4,133
    Quote Originally Posted by David Lyga View Post
    I have already tried adding Kodak Anti-Cal to no effect.
    The amount of Anti-Calcium used depends on the pH of the developer. More is needed for D-72 than for D-76. How much did you use?
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  2. #12
    David Lyga's Avatar
    Join Date
    Nov 2007
    Location
    Philadelphia, PA USA
    Shooter
    35mm
    Posts
    1,347
    Gerald (and others): I have achieved success. I have some old Kodak Anti-Calcium (sodium tetraphosphate) and the trick is to add it to the water BEFORE you add the sodium carbonate! If you add it AFTER cloudiness results there will be no effect.

    This past weekend I did lots of experimentation and got the requirement down to an astounding 0.1 g sodium tetraphosphate per liter of developer. You have to 'prepare' the water this way and I did this many times to confirm my results. I mixed one gram of the sodium tetraphosphate into 100ml of water to make a stock solution. Then I add 10ml of this stock to one liter of water to prepare the water, then add the chemicals for the developer (yes, even for an alkaline paper developer). I am truly amazed with how clear, suddenly, both my solutions (and life!!!) have become. Thank you all, especially Gerald Koch.

    Since Kodak Anti-Cal is no longer made is there another convenient source? Any way a large supermarket can have this in another product? Or is it necessary to buy it online? I have had a darkroom since I wa 14 (1964) and this discovery is truly revelatory. - David Lyga
    Last edited by David Lyga; 05-14-2012 at 08:39 AM. Click to view previous post history.

  3. #13

    Join Date
    Jul 2010
    Location
    Southern USA
    Shooter
    Multi Format
    Posts
    4,133
    The two suppliers that I use most often are www.chemistrystore.com and www.techcheminc.com. The Chemistry Store sells supplies for soap making but many of the chemicals are also used in photography. For example, sodium sulfite, sodium carbonate, sodium hydroxide, sodium thiosulfate, ... For basic chemicals they are very reasonable. BE SURE TO VISIT THE .COM SITE AND NOT THE .NET SITE WHICH IS ANOTHER COMPANY.

    The other company Tech Chem sells photographic chemicals and I buy my metol, hydroquinone, and Dimezone from them.

    The price per pound drops very quickly the more that you buy. TCS smallest size of Calgon is 10# for $36.60 while TCI sells 1# for $14.40.

    I find The Photographer's Formulary to be overpriced and some of their chemicals of questionable purity.

    Calgon and other pyrophosphate chelating agents slowly hydrolyse in solution. Even if 0.1 g/l works you may want to use the amount that Kodak recommends. The speed of hydrolysis is dependant on pH and so faster in D-72 than D-76.

    Calgon company used to sell just the pure chemical for clothes washing but the last time I looked they sell onjly the perfumed stuff for personal bathing. This product also contains other ingredients which could harm negatives and prints.
    Last edited by Gerald C Koch; 05-14-2012 at 04:45 PM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  4. #14
    David Lyga's Avatar
    Join Date
    Nov 2007
    Location
    Philadelphia, PA USA
    Shooter
    35mm
    Posts
    1,347
    If anyone wants to part with any Kodak Anti-Cal (sodium tetraphosphate) please contact me with quantity and price (zip 19103). As you can well see below, prices are quite reasonable, 'only' about $500 USD for slightly over one avoirdupois pound (500g). Perhaps the white powder is either competing with gold or is perceived as being a substitute for 'street value' Cocaine. Shipping and handling, alone, from Long Island to Philadelphia, is an astounding $110. At 62 I sitll do not understand life. - David Lyga


    Dear David,



    Thank you for your inquiry.

    We are pleased to quote as follows:



    Quote Number: BCU2827

    (Please indicate the quote number when you place an order)

    (This quote valid is valid within 30days).



    Product Name:Sodium Tetraphosphate

    CAS Number: 7727-67-5

    Quantity:500g

    Price(USD): 390


    Shipping fee: 80

    Handling fee:30



    Lead time:in stock



    Goods are shipped upon receipt of order.



    To order, we require a purchase order or a full advance payment. You may send the purchase order to us either by email: sales@bocsci.com .



    For custom synthesis project, 50% upfront payment is needed to initiate the project.



    Please contact me should you require any additional information.

    Our billing and mailing address:



    Creative Dynamics INC, BOC SCIENCES

    45-16 Ramsey Road

    Shirley, NY 11967, USA

    Tel: 631-504-6093

    Fax: 631-614-7828

    Email: sales@bocsci.com
    Last edited by David Lyga; 05-15-2012 at 10:07 AM. Click to view previous post history.

  5. #15
    desertrat's Avatar
    Join Date
    Aug 2005
    Location
    Boise, ID
    Shooter
    Multi Format
    Posts
    202
    Images
    10
    The important thing to realize here is that it's not necessary to obtain sodium tetraphosphate. Sodium hexametaphosphate (industrial calgon) works, is much easier to obtain, and is much less expensive. If the company you contacted is a distributor of laboratory chemicals, that would explain the price. Laboratory chemicals are very expensive.
    Happiness is a load of bulk chemicals, a handful of recipes, a brick of film and a box of paper. - desertrat

  6. #16

    Join Date
    Jul 2010
    Location
    Southern USA
    Shooter
    Multi Format
    Posts
    4,133
    Sodium tripolyphosphate can also be used to chelate calcium. The Chemistry Store sells it for $13.40 for 5 pounds.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  7. #17

    Join Date
    Sep 2002
    Location
    Oregon and Austria
    Shooter
    4x5 Format
    Posts
    883
    I fail to see why one would go to the trouble of buying and shipping yet another chemical (effective or not) even at a "reasonable" price when the entire problem is easily solved by just using de-mineralized or distilled water, which is available at your local supermarket or in vending machines for just a few cents a gallon...

    Sequestering agents make sense for big companies producing consumer mixes for which they cannot control the quality of water used for mixing.

    You can easily, and therefore do not need a sequestering agent if you just use pure(r) water.

    Cheaper and better all around I would think.

    Best,

    Doremus

    www.DoremusScudder.com

  8. #18
    David Lyga's Avatar
    Join Date
    Nov 2007
    Location
    Philadelphia, PA USA
    Shooter
    35mm
    Posts
    1,347
    Just seeing all the options.

    The cheapest bottled water here in Philadelphia is at the dollar store: $1 per gallon. Certainly that is affordable but I also wanted to read all the options. I always used proprietary formulae (D-76, Dektol) and did not realize that the sequestering agent was already included in the pre-mixed package. Now I know. I was so surprised at seeing the cloudy mixture that I had to nail the reason down. I now have that list of options. Again, thanks all. - David Lyga

  9. #19

    Join Date
    Jul 2010
    Location
    Southern USA
    Shooter
    Multi Format
    Posts
    4,133
    Here is information on four chelating agents for calcium and magnesium

    tetrasodium pyrophosphate Na4P2O7 Ca (poor) Mg (very good)
    sodium tripolyphosphate Na5P3O10 Ca (good) Mg (good)
    sodium tetraphosphate Na6P4O13 Ca (good) Mg (good)
    sodium hexametaphosphate (NaPO3)6 Ca (excellent) Mg (poor)
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin